Typewriting apparatus



July 24, 1962 A. w. SCRIBNER 3,045,796

TYPEWRITING APPARATUS Filed July 14, 1961 INVENTOR ALBERT W. SCRIB ER 3,045,796 TYPEWRITKNG APPARATUS Albert W. Scribner, West Hartford, Conn, assignor to Royal McBee Corporation, Port Chester, N.Y., a corporation of New York Filed July 14, 1961, Ser. No. 124,150 9 Claims. (Cl. 197-57) This invention relates to typewriting apparatus; more particularly it relates to typewriting apparatus characterized by a type carrier operatively mounted on a single type action common to and operable by each of a plurality of individual controls to effect printing; and specifically it relates to a typewriting apparatus wherein positioning of a selected type on the aforesaid type carrier is effected simultaneously with and by the movement of the type action to printing position.

Typewriting apparatus heretofore known may be categorized into two types, i.e., a matrix type wherein all of the type is on a common carrier and a bar type characterized by a plurality of type bars. In the matrix type apparatus selection of a character involves the production of a code representative of a character, the translation of the code into a movement of the matrix to position a type thereon, and the actuation of the matrix itself, or of a cooperating hammer to effect printing. As is apparent the train of events is necessarily serial and generally involves complex apparatus to selectively position the matrix. In the bar type apparatus selection of one of the plurality of type bars occurs simultaneously with key depression and the selected bar is driven through a printing stroke. The drawback of the latter typewriting apparatus is the duplication of parts necessitated by the fact that a bar must be provided for each character.

The typewriting apparatus in accordance with the instant invention exhibits the characteritsics of a matrix type apparatus without its complicated positioning structure and the characteristics of a bar type apparatus without its duplication of parts. Briefly the instant invention comprises a single type action or bar with which a common type carrier is operatively associated. The selection of a type on the type carrier is effected directly by a control, manually or automatically operated, which simultaneously effects the movement of the bar to print position; the positioning of the selected type on the type carrier being effected simultaneously with and by the movement of the bar to a print position.

An object of the invention is to provide a simple low cost typewriting apparatus.

Another object of the invention is in the provision of a typewriter apparatus having the advantages of matrix and bar type machines without the drawbacks attendant thereto.

A further object of the invention is to provide a single action typewriter wherein movement of the action positions a type carrier associated therewith to thereby position a selected type thereon.

A further object of the invention is in the provision of typewriting apparatus wherein the selection of a character to be printed initiates a type action common to and associated with a full complement of type characters and wherein the positioning of the type character selected is effected simultaneously with and by the movement of the type action.

Other objects and many of the attendant advantages of this invention will be readily approciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof and wherein:

Patented July 24, 1962 FIGURE 1 is a view showing in side elevation a single action typewriter apparatus having a common type carrier in accordance with the invention;

FIGURE 2 is a perspective view of elements shown in FIGURE 1;

FIGURE 3 is a side elevational view showing a typewriter key and associated elements;

FIGURE 4 is a schematic diagram of circuitry associated with the apparatus; and

FIGURE 5 is a view of a modification of the novel typewriting apparatus.

Referring now to the drawings there is shown in FIG- URE 1 a single type action generally designated by reference 11 which is adapted to be driven against a platen 12 to effect a printing through an inked ribbon (not shown). The platen is mounted on a carriage movable relative to the plane of the action under control of a suitable escapement as will be understood in the art.

More particularly the single type action comprises a bar 13 fulcrumed between frame members 14 and 15 on a cross shaft 16 suitably mounted in the frame members. The forward ends of the frame member are provided with projections 17 which support between them a pad or headrest 18 which cooperates with an extension 19 of the bar whereby the bar is supported in the rest position shown. The fulcrum end of the bar is formed with a crank arm 23 which extends angularly from the bar proper. A link 24 is secured to the crank arm and to a siutable power source, e.g. the armature 25 of a solenoid 26, which upon energization will power the type bar to printing position.

Referring to FIGURES 3 and 4 the solenoid 26 may be energized as by the closure of a switch 27 effected by a common bail 28 actuated upon depression of any of the typewriter keys 29 which are mounted on a fulcrum 30 common to all the keys. The circuitry associated with solenoid 26 and switch 27 whereby power is supplied to the solenoid may be similar to that shown in Patent No. 2,891,649 to W. L. Peterson wherein operation of the switch effects the discharge of a capacitor 32 through the solenoid; the capacitor being recharged by a power source 33 upon return of the switch to normal position.

Referring again to FIGURE 1 the type bar fulcrum shaft 16 rotatably mounts a pulley 34. Similarly a shaft 35, secured at the other end of the type bar, rotatably mounts a pulley 36. A drum 37, rotatably mounted on a shaft 38 secured between frame members 14 and 15 and substantially below shaft 16, contains a spiral spring (not shown) secured to the drum and to the shaft in a well known manner whereby rotation of the drum through power in one direction, e.g., clockwise, winds the spring, and when the drum is released, the spring unwinds and returns the drum in a counterclockwise direction to its normal position. As shown in FIGURES 1 and 2 a flexible dimensionally stable belt 42, secured at one end to and wound about the spring drum 37, extends around pulleys 34 and 35 and is secured to a fixed anchor shaft 43 secured between frame members 14 and 15 between and below pulleys 34 and 35. The side of the belt opposite the pulley side is provided with type characters 44, as shown in FIGURE 2, of any suitable metal or plastic material secured to the belt in any suitable manner. As shown in FIGURES 1 and 2 a guide plate 45 is secured below and parallel to the belt portion which extends between pulley 35 and anchor stud 43. Further, the frame members 14- and 15 are provided with a series of aligned holes 46 and 47, respectively, which series extend parallel to and above the belt portion between pulley 35 and anchor stud 43. Normally residing in the holes 47 of frame member 15 are fulcrum selector pins 48, the ends of which in their normal position do not extend over the belt 42. In their active position, the fulcrum selector pins 48 extend across the frame members, over the belt, and into a corresponding aligned hole 46 in frame member 14. The number of fulcrum pins 48 and holes corresponds to the number of characters accommodated on a keyboard. Each fulcrum selector pin 48 is secured to one end of a Bowden wire 49 whose other end (FIG- URE 3) is linked to an associated key 29. Upon depression of a key the Bowden wire pushes its associated pin into active position and when the key 29 is released, the key, Bowden wire and pin are restored by a return spring 31 attached to each key.

The action described will be sufficiently fast such that a cycle will ensue before a second key could be depressed and a second pin activated. However, as will be understood in the art, a ball lock may be provided to prevent the full depression of more than one key thereby to prevent the activation of more than one pin.

The operation of the above described apparatus is as follows: Upon depression of a key 29, a Bowden wire 49 associated therewith drives an associated pin 48 over the belt 42 into an associated hole 46. Simultaneously the common bail 28 operates switch 27 which effects the energization of solenoid 26 which drives the bar 13 to printing position. As the bar moves toward printing position the belt is pulled away relative to the spring drum shaft 38 an amount determined by the fulcrum pin selected thereby to position the type character on the belt corre sponding to the key depressed opposite the printing point when the bar reaches printing position, as is shown in dotted lines in FIGURE 1.

For the purpose of this disclosure the length of the belt when the action is in rest position may be considered to be that belt portion extending from the point of tangency with the spring drum 37 to the anchor 43 and when the action is at the printing position its length may be considered to be its rest position length plus the length unwound from the spring drum during its clockwise movement. Hence movement of the action may be said to increase the effective length of the belt.

For example, if the letter F is to be printed the sixth pin 48 to the right of anchor 43 will have been selected. It is to be noted in the figure that a point 51 on the belt, normally tangent to pulley 36 is a distance d +1rr away from the sixth pin and therefore will, when the bar reaches printing position, reside at a position the same distance d +1rr away from the fulcrum pin selected, r being the radius of pulley 36. Further point 51 on the positioned belt will be a distance d away from the point of tangency of the positioned belt with the platen 12. Hence when the bar 13 reaches printing position the belt 42 will have been pulled away relative to the spring drum shaft 38 a distance d thereby positioning the sixth type character on the belt before the printing point on the platen 12.

In accordance with the invention the geometric relationship of the spring drum, pulleys, and anchor is such that virtually all of the belt movement is accomplished before the bar reaches print position whereby the belt will be substantially stationary when it strikes the printing point on the platen. After printing the bar 13 is returned to normal by the counterclockwise movement of the spring drum as the spring therein unwinds.

While the spring drum 37 has been shown mounted separately it could just as well be incorporated on shaft 16. The modification shown in FIGURE 1, however, permits a greater displacement of the belt 42 and therefore the accommodation of a greater number of characters 44 thereon. Further the geometry can be changed from that shown to accommodate greater belt displacement e.g. the action could be designed to move through an are greater than 90.

A modification of the novel typewriting apparatus is shown in FIGURE wherein a flexible dimensionally stable belt 42 is secured to a spring drum 53 mounted on the fulcrum shaft 16 of the type bar, looped around a Cal pulley 54 mounted on the free end of the type bar, and anchored as at 43. In this modification the belt 42 is longitudinally displaced as the bar moves as described with respect to FIGURES 1 and 2. In this modification, however, the type characters 44 are secured to a continuous belt 55 looped around pulleys 5'7 and 58 respectively, the former secured coaxially and for movement with spring drum 53; the latter being free to move independently of pulley 54. Pulley 57 is of larger diameter than the diameter of spring drum 53 whereby a mechanical advantage is gained as determined by the ratio of the radii 1' and r, of pulley 57 and spring drum 53. Hence, for a given displacement of belt 42, the type carrier belt 55 Will longitudinally translate as the type bar moves, an amount greater than the displacement of belt 42. This modification permits the accommodation of a greater number of characters since the displacements involved are larger.

It should be understood therefore that the foregoing disclosures relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purposes of the disclosure which do not constitute departures from the spirit and scope of the invention.

The invention claimed is:

1. Typewriting apparatus comprising a flexible dimensionally stable belt having a plurality of type characters secured thereto along its long dimension, a first fixed support, yieldable means for securing one end of said belt to said first support, a second fixed support, said other end of said belt being secured to said second support, and means operative in response to the selection of a type character for selectively increasing the effective belt length between said supports whereby a selected type on said belt is positioned before a reference point.

2. Typewriting apparatus comprising a flexible dimensionally stable belt having a plurality of type characters secured on one side thereon along its long dimension, a first support, yieldable means for securing one end of said belt to said first support, a second support for fixedly securing the other end of said belt, drive means operative to increase the effective belt length between said supports whereby said belt is longitudinally displaced a constant distance relative to said first support, and means operative in response to the selection of a type character for selectively increasing the amount of longitudinal displacement of said belt over and above said constant amount whereby a selected type character thereon is positioned before a reference point.

3. Typewriting apparatus comprising a flexible dimensionally stable belt having a plurality of type characters attached thereto along its long dimension, a first support, means for yieldably securing one end of said belt to said first support, a drive arm fulcrumed for movement through a predetermined arc, a pulley on the free end of said drive arm, a second support for anchoring the other end of said belt, said pulley being positioned between said supports and adapted to guide said belt, a plurality of fulcrum pins, means for introducing a selected one of said pins between said second support and said pulley whereby when said drive member moves through its are said belt is longitudinally displaced a selected distance relative to said first support thereby to position a selected type character thereon before a reference point at the end of said arcuate travel of said drive means.

4. Typewriting apparatus comprising a flexible dimensionally stable belt having a plurality of type characters secured thereto on one side along its long dimension, a bar adapted to be driven through a predetermined arc in response to the selection of a type character, a pulley on the free end of said bar, means for yieldably supporting one end of said belt and for anchoring the other end of said belt, said belt between said supports being guided by said pulley, whereby said belt will be longitudinally displaced relative to said means for yieldably supporting said one end of said belt as said bar is driven through its arc, means operative upon selection of a type character for initiating a drive cycle of said bar, and means operable upon selection of a type character for controlling the longitudinal displacement of said belt by said bar as it moves through its arc, whereby the type character selected will be positioned at a printing point at the end of said are of travel.

5. Apparatus as recited in claim 4 wherein said means for controlling the longitudinal displacement of said belt comprises a plurality of pins, one associated with each type character, said pins being positioned along a line parallel to said belt betwen said belt anchor and said pulley, said pins when selectively operatively positioned being operable to intercept said belt as said ba-r moves through its arc.

6. Type positioning apparatus comprising a bar adapted to be driven through a predetermined are from a rest position to a printing position, a flexible dimensionally stable belt, means for yieldably securing one end of said belt, means for anchoring the other end of said belt, a pulley on the free end of said bar, said belt being looped around said pulley, whereby during movement of said bar said belt is longitudinally displaced, and a plurality of selectors adapted to intercept said belt between its anchored end and said pulley.

7. Apparatus as recited in claim 6 wherein said belt has a plurality of type characters fixed thereto 011 one side along the long dimension of said belt.

8. Apparatus as recited in claim 6 further comprising a second pulley coaxially mounted on the free end of said bar, wherein said means for yieldably securing said belt comprises a spring drum coaxially mounted on the fulcrum shaft of said bar, a third pulley having a diameter larger than said spring drum diameter coaxially mounted on said fulcrum shaft for movement with said spring drum, and a continuous flexible dimensionally stable type carrier looped around said third and second pulleys, said type carrier having a plurality of type characters along its longitudinal dimension secured thereto.

9. Typewriting apparatus comprising a type bar fulcrumed about one end for movement from a rest position through a predetermined arc to a printing position, a spring drum, a pulley mounted on the free end of said type bar, a flexible dimensionally stable belt secured to said spring drum looped around said pulley and secured to a fixed anchor, a plurailty of pins adapted to be selectively positioned between said anchor and the free end of said bar so as to intercept said belt as said bar moves toward printing position, means for selecting said pins, and means simultaneously operable with the selection of a pin for driving said type bar, said belt having a plurality of type characters secured thereto along its long dimension whereby during movement of said bar to printing position said belt is longitudinally displaced an amount such that the type character corresponding to the selected pin is positioned at said printing position.

References ited in the file of this patent UNITED STATES PATENTS 495,604 Sorg Apr. 18, 1893 657,806 Adams Sept. 11, 1900 761,210 Cottrill May 31, 1904 

